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Homotopy categories of unbounded complexes of projective modules

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 نشر من قبل Yuji Yoshino
 تاريخ النشر 2018
  مجال البحث
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 تأليف Yuji Yoshino




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We develop in this paper a stable theory for projective complexes, by which we mean to consider a chain complex of finitely generated projective modules as an object of the factor category of the homotopy category modulo split complexes. As a result of the stable theory we are able to prove that a complex of finitely generated projective modules over a generically Gorenstein ring is exact if and only if its dual complex is exact. This shows the dependence of total reflexivity conditions for modules over a generically Gorenstein ring.



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